Traditional touch display devices are mainly formed by forming a touch sensor on a substrate (for example, a glass substrate) to form a sensor glass and then attaching the sensor glass to a protective layer and a LCD (liquid crystal display), and the object of touch display is achieved.
As shown in FIG. 1, the touch electrode structure in the touch sensor comprises: a plurality of electrode assemblies 61′ formed on the substrate 60′ and electrode pins 62′ for connecting a touch circuit, wherein each electrode assembly comprises two triangular electrodes 611′ insulated from each other and complementarily crossing with each other, and each electrode is connected with an electrode pin. Correspondingly, the section structure of the touch substrate along the direction A-A′ in FIG. 1 is shown in FIG. 2. Generally, the distance between the electrode pins is within the range of 6-8 mm, while the gap (the distance between the adjacent triangular electrodes in FIG. 1) between ITOs is within the range of 50-100 μm. Such an electrode structure design can meet usual application needs.
However, in the above electrode structure design, there may exists the possibility that a touch point cannot be reported normally, as shown in FIG. 3, wherein, A1, A2 and A3 respectively represent the touch positions of a finger on a touch screen. When A1 and A2 are touched, as two adjacent electrodes are touched at the same time, the coordinates can be correctly calculated. However, when A3 is touched, only one electrode is touched, the coordinates of the position A3 cannot be correctly calculated. In practical use, the situation of touching A3 cannot be avoided, for example, the test situation of a touch width of 5 mm or the touch by the fingertip of little finger.
Report rate is an index of evaluating touch sensitivity, and the higher the report rate is, the better the sensitivity is, and then the position of a touch point can be reflected more correctly. From the above analysis, the above electrode structure design has some defects and cannot ensure correct report of each touch point, that is, it cannot ensure that the coordinates of the touch position of each touch can be correctly calculated.